1. Field of the Invention
There has been provided a serpentine heat exchanger having a first serpentine tube block (12a) comprising one or more adjacent first serpentine tube sections with parallel through-flow and a second serpentine tube block (12b) disposed behind the first and comprising one or more adjacent second serpentine tube sections with parallel through-flow. At least one of the second serpentine tube sections is connected in series for flow purposes via a diversion section (10, 11) to a first serpentine tube section lying adjacent thereto.
2. Description of Related Art
Serpentine heat exchangers are disclosed in laid-open application DE 197 29 497 A1. These heat exchangers contain a plurality of tube blocks arranged one behind the other in a depth direction. Each tube block consists of a plurality of serpentine flat tube runs adjacent in a vertical direction of the block. All of the flat tube runs of all tube blocks open into appropriate collection chambers in a manner such that an air-conditioning system refrigerant can flow through them in parallel. In order to achieve a more uniform heat distribution within each tube block, provision can be made for an inlet tube side of each flat tube run to border an outlet side of a neighboring flat tube run.
DE 172 29 497 A1 also discloses a type of heat exchanger that contains one inlet-side tube block and one outlet-side tube block. The inlet-side tube block and the outlet side tube block are disposed one behind the other in the depth direction of the block and are formed, integrally, by respective halves of U-shaped flat tubes. The two flat tube halves are in fluid connection via the U-bend region which consequently forms a corresponding fluid diversion region. The two tube blocks each consist of adjacent, linear flat tube sections and are connected in series for flow purposes via the fluid deflection region. In this arrangement, the two flat tube halves are twisted relative to the U-bend region in a manner such that they lie perpendicularly to the vertical direction of the block, while the U-bend region lies parallel or at an acute angle to the vertical direction of the block. Instead of the U-shaped flat tubes, two linear flat tubes may be provided instead with a diversion channel replacing the U-bend region. The flat tubes open on the appropriate side of the block into the diversion channel. On the inlet and outlet sides, the flat tubes with parallel through-flow open into a connecting tube. The connecting tube is subdivided by means of a transverse partition into two separate collection chambers lying one behind the other in the depth direction of the block.
A flat tube evaporator for a motor vehicle air-conditioning system, similar to the above-mentioned heat exchanger type, is disclosed in laid-open application DE 197 19 261 A1. The evaporator described therein contains a tube block of linear, multichannel flat tubes. On one side of the block, two separate, adjacent collection chambers are provided, into which each flat tube opens with one part of its plurality of fluid channels. On the opposite side of the block, individual diversion channels for each flat tube or a common channel for all flat tubes are provided, in order to divert the flow coming from the inlet-side flat tube channels into the outlet-side flat tube channels.
Therefore, one object of the invention is to provide a serpentine heat exchanger, of the general type referred to above, which can produce a comparatively homogeneous distribution of heat, and therefore of temperature, and which is relatively simple to produce.
In accomplishing the objects of the invention, there has been provided according to one aspect of the invention a heat exchanger comprising a first serpentine tube block comprising at least one serpentine tube section; a second serpentine tube block comprising at least one serpentine tube section; and a diversion section; wherein the second serpentine tube block is arranged behind the first serpentine tube block and wherein at least one serpentine tube section of said second serpentine tube block is in serial fluid communication with at least one serpentine tube section of said first serpentine tube block via the diversion section.
In accordance with an additional aspect of the invention, there is provided a heat exchanger comprising a front tube block; a rear tube block arranged in serial fluid communication with the front tube block; a collector tube; a partition plate arranged to divide the collector tube into a front collection chamber and a rear collection chamber; a front flat tube channel in fluid communication with the front collection chamber; a rear flat tube channel in fluid communication with the rear chamber and arranged to allow for parallel flow along with the front flat tube channel; front serpentine flat tubes in fluid communication with the front flat tube channel; rear serpentine flat tubes in fluid communication with the rear flat tube channel; a front diversion tube piece in fluid communication with the front serpentine flat tubes; a rear diversion tube piece in fluid communication with the rear serpentine flat tubes; an outlet side front tube block in fluid communication with the front diversion tube piece; an outlet side rear tube block in fluid communication with the rear diversion tube piece such that a medium may flow in an opposite direction to a medium flowing through the outlet side front tube block; a first outlet side collection chamber in fluid communication with the outlet side front tube block; a second outlet side collection chamber in fluid communication with the outlet side rear tube block; and a collector pipe in fluid communication with the first and second outlet side collection chambers.